docs: def from_response(cls, response_data):
          """
          Factory method to create a Mail instance from a Guerrillamail response
          dict.
          """
          identity = lambda x: x
          return Mail(**_transform_dict(response_data, {
              'guid': ('mail_id', identity),
              'subject': ('mail_subject', identity),
              'sender': ('mail_from', identity),
              'datetime': ('mail_timestamp', lambda x: datetime.utcfromtimestamp(int(x)).replace(tzinfo=utc)),
              'read': ('mail_read', int),
              'excerpt': ('mail_excerpt', identity),
              'body': ('mail_body', identity),
          }))